Testing EQ6-R mount on Carina Nebula

User images created with StarTools.
Post Reply
Startrek
Posts: 357
Joined: Mon Dec 30, 2019 3:49 am

Testing EQ6-R mount on Carina Nebula

Post by Startrek »

I’ve spent the last few weeks working on my EQ6-R mount to reduce backlash and have re orientated my Newt to achieve better balance in the pursuit of improved tracking and guiding.
Adjusted the worm gears in Ra and Dec ( took time to fine tune and eliminate micro binding ) plus checked and tightened Ra and Dec motor drive belts
I’ve owned the mount for over 3 years and never touched anything, just straight out of the box
Sunday night offered an hour or so of clear skies so chose the NGC 3327 Carina Nebula as my test target due to being a huge nebula with a comprehensive Star field
Tracking and guiding ran extremely well with my total rms error being 0.45 lowest and 0.60 highest throughout the hour session ( previously my guiding was ranging from 0.70 to 0.85 on good to average nights )
I still need more testing across various parts of the sky to quantify the work done on the mount but these initial results are promised to say the least.There were no excursions in either axis and the mount recovered within 10 sec from dithering.

Southern Hemisphere Skies
Waning Moon 95%
NexDome Obs
8” f5 GSO Newt
EQ6-R mount
Payload nearly 15kg
ZWOASI2600MC Gain 0 cooled to -10C
Optolong L Extreme filter
Baader MPCC Coma Corrector
18 x 3 minute dithered guided subs
40 x Flats
50 x Bias
Tracking and Goto EQMOD and Ascom Stellarium
Framed focused and captured with APT
PHD2 Multistar guiding
Subs reviewed in Astap
Stacked in DSS
Processed in Startools V1.7 Compose OSC Bi Color
A few SHO versions using Matrix in Color module

Comments most Welcome
Thanks
Attachments
3ACB2E42-244D-4A8A-8968-F53A9F2D4E73.jpeg
3ACB2E42-244D-4A8A-8968-F53A9F2D4E73.jpeg (507.99 KiB) Viewed 1449 times
7545A463-67F7-417C-999A-9F740635DD72.jpeg
7545A463-67F7-417C-999A-9F740635DD72.jpeg (504.85 KiB) Viewed 1449 times
D0B7D1BA-1F8D-40D7-A090-912FB515E623.jpeg
D0B7D1BA-1F8D-40D7-A090-912FB515E623.jpeg (519.55 KiB) Viewed 1449 times
Mike in Rancho
Posts: 1152
Joined: Sun Jun 20, 2021 10:05 pm
Location: Alta Loma, CA

Re: Testing EQ6-R mount on Carina Nebula

Post by Mike in Rancho »

Nice target choice and impressive bicolors, as usual. :thumbsup:

You probably did it for a reason, such as to help reveal some of the brighter hue of the bicolor against the darker regions, but in its own very bright triangle up top, it seems a bit washed out, perhaps? If I peek closely, it seems that there may be great extra detail hidden in there. Most noticeable in your green version.

No version 1.8 yet? The new HDR's controls might work really well with this. Also a couple of the tricolor matrices were tweaked in last night's release. Or at least, two descriptions and one matrix, though I think that one was way down in HOS or something like that.

What kind of improvement did you set up for the Newt balance? I imagine have more room for adjustment than I do. With the little Orion 6 f/4, there's really only one good way to put it in the clamshell rings, which is straddling the focuser. Right now I use it with the focuser/camera and guide scope/camera in a "V" across the top to equal each other out. The guide scope is in the finder scope bracket, and I'm just going with no finder. I don't think I could pull off a "camera down" setup without some moderate re-engineering.
Startrek
Posts: 357
Joined: Mon Dec 30, 2019 3:49 am

Re: Testing EQ6-R mount on Carina Nebula

Post by Startrek »

Mike,
Thanks
For under an hour of data I’m fairly pleased with the level of detail but I do agree hat more dynamic range could have been extracted through some of the modules, I tend to be on the conservative side.
Here’s some photos of my current set up
Balancing has improved immensely compared to the old configuration ( camera at 2 o’clock and finder at 10 o’clock) I’ve totally removed my finderscope due to the new configuration as I never used it much anyway , just for some planetary imaging alignment.
The mounts can be precisely balanced now , it allowed me to remove an extension CW bar and moved the 3 x 5.1kg CW’s closer to the mount for improved moment of inertia
I certainly now recommend this new 6 o’clock/ 12 o’clock orientation for Newts rather than the 2 o’clock/ 10 o’clock arrangement before.
Also minimising backlash on worm gears and drive belts is a massive improvement but it does take time , skill and patience
Clear Skies
Martin
Attachments
F7F7D7E4-B830-4A28-91D1-A8F65ECB630A.jpeg
F7F7D7E4-B830-4A28-91D1-A8F65ECB630A.jpeg (473.37 KiB) Viewed 1439 times
46BC6788-2584-4136-92A3-1CCB4A81D6C7.jpeg
46BC6788-2584-4136-92A3-1CCB4A81D6C7.jpeg (530.07 KiB) Viewed 1439 times
Mike in Rancho
Posts: 1152
Joined: Sun Jun 20, 2021 10:05 pm
Location: Alta Loma, CA

Re: Testing EQ6-R mount on Carina Nebula

Post by Mike in Rancho »

Thanks for the description and photos, Martin. :obscene-drinkingcheers:

Yes, 10 and 2 is what I've been doing. I'm not sure I have other reasonable options, either. I do have a tickler in with Agena in order to get a second 13-inch Vixen bar, which can go opposite the one I have below for mounting, but I'm not sure that'll allow me a camera down configuration.

Rather, I'd probably need to get a couple 8-inch bars and reconfigure the main OTA rings, and then hope I can still get fore-aft balance.

Oh well, pretty good guiding right now anyway, or so it seems. Especially if I use NINA's TPPA, which I just started doing. So far haven't tried it for anything else and am still using BYN.

Been a while since I've checked, but I have inspected my belts one time since the mod, and performed the backlash adjustment for both worms, after I could feel the clunks using the wiggle test. Seems solid right now. That said, I don't know what micro binding is or how I would look for that?
Startrek
Posts: 357
Joined: Mon Dec 30, 2019 3:49 am

Re: Testing EQ6-R mount on Carina Nebula

Post by Startrek »

Thanks Mike,
After you’ve done the Ra and Dec wiggle test for obvious backlash you can then check for micro binding
When you slew the mount at rate 6 for both Ra and Dec with the Synscan you listen very carefully the high pitch noise the motor drive and worm gear make. My Ra movement had a uniform sound through + 180 degrees but the Dec had some very slight fluctuations in sound towards one side of the slew. I then loosened the Dec carrier backed off or loosened the Dec adjusting grub screw ever so slightly ( 1/16 turn or less ) then tightened up the Dec carrier again.Performed a Dec slew test again and the faint sound fluctuations were gone , the mount slewed in Dec all the way around with uniform pitch same as Ra
That night guiding was the proof of my adjustments as both Ra and Dec were excellent very smooth with subtle corrections , Dec was almost flat lining , compared to the previous night same position in sky , Dec had noticeably bad backlash and Ra was acceptable
I just call the above tuning eliminating “micro binding”
I also heard the term from a Guy in the UK called “ Astrobloke”
Clear Skies
Martin
Mike in Rancho
Posts: 1152
Joined: Sun Jun 20, 2021 10:05 pm
Location: Alta Loma, CA

Re: Testing EQ6-R mount on Carina Nebula

Post by Mike in Rancho »

Thanks. :bow-yellow:

I will try that trick out and see how well it performs!
Post Reply